refactor: move brother_node development artifact to dev/test-nodes subdirectory

Development Artifact Cleanup:
✅ BROTHER_NODE REORGANIZATION: Moved development test node to appropriate location
- dev/test-nodes/brother_node/: Moved from root directory for better organization
- Contains development configuration, test logs, and test chain data
- No impact on production systems - purely development/testing artifact

✅ DEVELOPMENT ARTIFACTS IDENTIFIED:
- Chain ID: aitbc-brother-chain (test/development chain)
- Ports: 8010 (P2P) and 8011 (RPC) - different from production
- Environment: .env file with test configuration
- Logs: rpc.log and node.log from development testing session (March 15, 2026)

✅ ROOT DIRECTORY CLEANUP: Removed development clutter from production directory
- brother_node/ moved to dev/test-nodes/brother_node/
- Root directory now contains only production-ready components
- Development artifacts properly organized in dev/ subdirectory

DIRECTORY STRUCTURE IMPROVEMENT:
📁 dev/test-nodes/: Development and testing node configurations
🏗️ Root Directory: Clean production structure with only essential components
🧪 Development Isolation: Test environments separated from production

BENEFITS:
✅ Clean Production Directory: No development artifacts in root
✅ Better Organization: Development nodes grouped in dev/ subdirectory
✅ Clear Separation: Production vs development environments clearly distinguished
✅ Maintainability: Easier to identify and manage development components

RESULT: Successfully moved brother_node development artifact to dev/test-nodes/ subdirectory, cleaning up the root directory while preserving development testing environment for future use.

dev/env/node_modules/@noble/curves/src/p521.ts

@@ -0,0 +1,68 @@
+/*! noble-curves - MIT License (c) 2022 Paul Miller (paulmillr.com) */
+import { createCurve } from './_shortw_utils.js';
+import { sha512 } from '@noble/hashes/sha512';
+import { Field } from './abstract/modular.js';
+import { mapToCurveSimpleSWU } from './abstract/weierstrass.js';
+import { createHasher } from './abstract/hash-to-curve.js';
+
+// NIST secp521r1 aka p521
+// Note that it's 521, which differs from 512 of its hash function.
+// https://www.secg.org/sec2-v2.pdf, https://neuromancer.sk/std/nist/P-521
+
+// Field over which we'll do calculations.
+// prettier-ignore
+const P = BigInt('0x1ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff');
+const Fp = Field(P);
+
+const CURVE = {
+  a: Fp.create(BigInt('-3')),
+  b: BigInt(
+    '0x0051953eb9618e1c9a1f929a21a0b68540eea2da725b99b315f3b8b489918ef109e156193951ec7e937b1652c0bd3bb1bf073573df883d2c34f1ef451fd46b503f00'
+  ),
+  Fp,
+  n: BigInt(
+    '0x01fffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffffa51868783bf2f966b7fcc0148f709a5d03bb5c9b8899c47aebb6fb71e91386409'
+  ),
+  Gx: BigInt(
+    '0x00c6858e06b70404e9cd9e3ecb662395b4429c648139053fb521f828af606b4d3dbaa14b5e77efe75928fe1dc127a2ffa8de3348b3c1856a429bf97e7e31c2e5bd66'
+  ),
+  Gy: BigInt(
+    '0x011839296a789a3bc0045c8a5fb42c7d1bd998f54449579b446817afbd17273e662c97ee72995ef42640c550b9013fad0761353c7086a272c24088be94769fd16650'
+  ),
+  h: BigInt(1),
+};
+
+// prettier-ignore
+export const p521 = createCurve({
+  a: CURVE.a, // Equation params: a, b
+  b: CURVE.b,
+  Fp, // Field: 2n**521n - 1n
+  // Curve order, total count of valid points in the field
+  n: CURVE.n,
+  Gx: CURVE.Gx, // Base point (x, y) aka generator point
+  Gy: CURVE.Gy,
+  h: CURVE.h,
+  lowS: false,
+  allowedPrivateKeyLengths: [130, 131, 132] // P521 keys are variable-length. Normalize to 132b
+} as const, sha512);
+export const secp521r1 = p521;
+
+const mapSWU = /* @__PURE__ */ (() =>
+  mapToCurveSimpleSWU(Fp, {
+    A: CURVE.a,
+    B: CURVE.b,
+    Z: Fp.create(BigInt('-4')),
+  }))();
+
+const htf = /* @__PURE__ */ (() =>
+  createHasher(secp521r1.ProjectivePoint, (scalars: bigint[]) => mapSWU(scalars[0]), {
+    DST: 'P521_XMD:SHA-512_SSWU_RO_',
+    encodeDST: 'P521_XMD:SHA-512_SSWU_NU_',
+    p: Fp.ORDER,
+    m: 1,
+    k: 256,
+    expand: 'xmd',
+    hash: sha512,
+  }))();
+export const hashToCurve = /* @__PURE__ */ (() => htf.hashToCurve)();
+export const encodeToCurve = /* @__PURE__ */ (() => htf.encodeToCurve)();